Tool joint



June 5, 1934. F. J. HmmEFeLl'rr-:Rv

TOOL JOINT Filed June 12, 1930 2 shears-sheet 1 June 5 1934- F. J.HINDERLITER 1,961,763

TQOL JOINT Filed June l2. 1930 2 Sheets-Sheet 2 mxmmmmwxm INVENTORATTORNY Patented June 5, 1934 UNITED STATES PATENT oFFIc My inventionrelates to tool joints. and more particularly to a device of thatcharacter for coupling the sections of drill pipe employed in rotarywell drilling equipment, the present application constituting acontinuation in part of my pending application Serial No. 420,419 andNo. 447.258.

In rotary drilling the bit is suspended in the well hole on a tubularrod,'known as drill pipe l and formed in sections which are connected bycoupling devices known as tool joints, to provide a continuous passagethrough which mud-laden iiuid is delivered for cleaning the bit,softening the formation and ilushin'g the drillings from i 15 the wellhole.v The fluid, being delivered through the pipe under high pressure,is inclined to seek outlet through the joints and when a leak occurs thenne sand carried in suspension in the iluid grinds the metal over whichit ows and rapidly 2a eats away the wall of the joint, short circuiting'vthe fluid and thus interfering with 'the 'drilling operation. l

It is the object of my invention to obviate such interference with thedrilling operation and the loss incident to such'damage to the equipmentby scaling the pipe sections in the joints to prevent initial escapeoi'- fluid at the joints and thus obvia'te the destructive effectsresulting from continued leakage.

In accomplishing this and other objects of the invention, I haveprovided improved details of structure, the preferred form of which isillustrated in the accompanying drawings, wherein: Fig. 1 is .a centrallongitudinal section of a tool joint embodying my improvements andportions of drill pipe connected thereby.

Fig. 2 is a perspective. view of disassembled members of the joint inspaced relation and cut away to illustrate their construction.

Fig.' 3 is an enlarged detail view of a pipe-joint packing member incentral longitudinal section.

Fig. 4 is a similar view of the pin-box packing member. l 46 Fig. 5 is aview similar to Fig. 2, illustrating the invention. applied to a pipecollar.

Fig. 6 is a view of part of a'string of drill pipe as it appears in awell, showing the pipe sections connected by tool joints and the pipestring con..

l nected wtih ai drill pipe and the operating tool known as a griefstem", by tool jointsand coupling collars.

Fig. 'I-illustrates removal of drill pipe from a well and racking ofstandsof drill pipe in a derssrlck.

Fig. 8 illustrates application of `a stand of drill pipe to the part ofa string in a well.

Referring in detail to the drawings:

A tool joint as ordinarily constructed includes pin and box members 1,2, each including, at its outer end, a socket 3, for receiving the end 4of a drill pipe section 5 and having an intermediate, tapered wallportion 6 extending from near the outer Jend of the socket to near thebase thereof, and terminating at its inner end in a reducing throat 7leading to channel 8, 9 in sleeve portions 10, 11 of the respectivejoint members. The tapered wall portion 3 of: each socket member isthreaded from its outer end to near the throat 'l to cooperate withthreads on the tapered end of a pipe section, leaving an unthreadedportion 12 at the inner end of the socket, the outer ends 13 ofthesocket wall being unthreaded and ofV suincient interior diameter toprovide play of the pipe section and prevent shearing.

The inner 4, end of the box member v2 includes a tapered socket 14terminating in a transverse shoulder 15 `within the collar portion 11,and threaded from its outer end to near the shoulder for cooperationwith the threads on the pin 16 80 of the pin memberl of the joint. theinner end 17 of the socket wall being left smooth. The base of the pinis inset, forming a shoulder 18 for abutting against the inner end ofthe box member and limiting projection of the pin into the box socket. AA

With such construction projection of the pipe sections into the jointmembers except by restriction of the sockets, thereby enabling extremelytight connections oi' the pipes 90 with the joints, but projection ofthe pin into the box socket is limited by the shoulder 18, therebyinsuring against binding of the joint, and facilitating separation ofthe pipe at the joint when required during the drilling operation.

If the parts constructed as described. are without iiaw and assembledaccurately, they will usually confine the drilling iluid withoutleakage,

A but should the threads on the joint or pipe be outlet until suchquantity of the' iluid is short 110 circuited into the return line as toseriously in- Y ing for sealing the connections between the pipesections and joint members within the pin and box sockets, 19designatesa rubber or like ring having an exterior diameter to t easilyinto either of the like sockets 3 to a point near the base of thesocket, where it will extend about equally over the threads in thesocket and over the smooth surface 12, and having an interior diameterslightly less than that of the pipe sections and greater than thereduced channel 8, 9 in the pin and box members, the outer edge 20 ofthe ring being slightly convex and the inner edge 21 more markedlyconcave for purposes presently described. 'At its concave edge the ringis inset for a part only of its depth to form a seat 22 for `a stiieningring 23, preferably of rigid metal, having an interior diametercorresponding with that of the ring so that their surfaces arecoextensive.

osi

The ring 24 for sealing the connection between the pin and box of thejoint, also composed, of rubber or like material, is of a thicknessapproximately equal to the width of the seat 15 in the socket 14 of thebox member so that its interior diametercorresponds to the diameter ofthe channel 8 9, and of a depth to be compressed against the seat 15 bythe end of the pin 16 when the pin is fully threaded into the box socket14, i. e., until the shoulder 18 on the pin member engages the edge ofthe box member (Fig. 1) Embedded in the ring 24 are a number of atstiiening rings 25, preferablyof rigid metal, arranged in spacedrelation and with their faces parallel withthe edges of the ring, formaintaining the general contour of the ring and preventing its collapseunder heavy pressure on its opposite edges.

With the parts constructed as described, the pipe socket rings areinserted into their sockets, with the concaved faces directed inwardlyand the pipe sections screwed into the sockets to contact with the outerconvex edges of the rings,

the :dat edges of the pipe sections irst` engagin such wall, at the sametime pushing the ring inwardly into the converging base of the socketand compressing the body of the ring between the wall of the socket andthestifi'ening and retaining ring 23. v

With the pipe sections connected to the joint members, when the jointmembers are to be coupled a packing ring 24 is located in the seat 15 ofthe box member and the pin on the pin member threaded into its socket inthe box member, the end of the pin engaging the ring as the. pin reachesits set'position and compressing the ring laterally against the wall ofthe socket, so that when travel of the pin is interrupted by engagementof the shoulder 18 with the end of the box member, an effective seal hasbeen established between the pin and box members, the stiiening ringsembedded in the packing ring preventing the latter from collapsinginwardly under the lateral distortion due to the extreme pressure.

When the parts are so assembled, drilling uid circulating in the pipeunit underfhigh pressure, engaging the concave faces of the outer ringsof the joint, presses such portions of the rings rmly against the wallsof the sockets to promote the sealing effect.

With the sealing rings constructed, assembled, and functioning asdescribed, the threaded connections and any defects in the material atthe joints are sealed by the rings to preclude bypassing of the fluid;high pressure on the fluid being converted to an aid in maintaining thejoint instead of promoting its destruction in the manner common to suchjoints of ordinary construction.

The form of coupling illustrated in Fig. 5 is employed for connectingcertain types of drills with the drill pipe in connection with a tooljoint and for connecting the pipe with the operating or grief stem atthe top of the well, also in connection with a tool joint.

In the figures of the drawings illustrating use of my invention, 27(Fig. 6) designates a well'hole in process of formation by a bit 28attached to the lower section 5 of a string of drill pipe by a tooljoint and collar; the individual sections of the pipe being coupled bytool joints 1-2; the upper pipe section being shown connected with theoperating tool or grief stem" S by a tool joint and collar.

In Figs. 7 and 8, D designates a derrick havin a floor F, S a spider inthe drilling table T suspending part of the string of pipe in the well,and E an elevator whereby the pipe is let into and removed from thewell, here shown as suspending a stand of pipe which has been4 eitherjust disconnected from the string for racking on the derrick floor orpicked up from the rack for application to the string as in the usualpulling or letmember 2 at its upper end has been sunk in the hole formedby the drill bit, a second section of similar pipe carrying a pin jointmember at its izo When the rst section of pipe carrying a box lower endis connected with the pipe in the well 13b by threading the pin into thebox to extend the length of the pipe. Drilling is then resumed, andother sections of pipe are added as the drilling progresses. v

As the well hole deepens, strata are encountered which rapidly dull orotherwise aiect the bit so that it is frequently necessary to pull thepipe out of the holel for replacement or repair of the bit. .When thewells are relatively shallow pulling and replacement of the pipe is nota serious matter, but when the hole is extended to great or substantialdepths delay in separating and again connecting each individual. sectionfrom and to the string would seriously delay the operarate and assemblethe stands instead of the individual pipe sections. ,l

While the collar type of couplingl provides a secure connection for thepipe sections, it would be impractical for use asa joint connectionbecause of delay incident to the threading vand unthreading ,operations,of liability of the ne threads to jam when the pipe sections are set inthe collar, and liability of the threads of the mating members to weldfrom heat generated by s friction during the threading operation.

Consequently the different connection or tool joint, is employed forconnecting the pipe joints or sections, each tool joint including pinand box members connected respectively with upper and lower sections ofpipe by the relatively flne threads (about eight to the inch) andconnected together by coarse threads (about four or five to the inch) sothat the joints may be connected or disconnected by about ve revolutionsof one member relative to the other, as distinguished from theapproximately twenty-four turns required for making or breaking theconnection between a pipe section with a collar. The coarser threads ofthe tool joint are also much less liable to distortion from impact ofone member with the other during the setting operation, 'and overheatingwill not occur during the relatively short assembling operation.

During drilling of a well with rotary tools, mud laden fluidis'circulated down through the drill pipe and bit and up the well holeto wash the bit and remove cuttings from the hole. When the hole isshallow circulation may be maintained with relatively low pump pressurebut as the hole deepens greater pressures are required, the presentpractice in drilling wells to depths of six thousand feet and morerequiring pressures up to and exceeding one thousand pounds to thesquare inch. Fluid circulated at pressures ranging from a few hundredpounds up to the ex. tremely high pressures will seek outlet from thedrill pipe through any defective joint or coupling, and any minute leakthrough a joint or coupling israpidly increased from grinding of thewalls of the connection by ne sand in the fluid, When this occurs thefluid by-pass through the leak and circulation inthe part of the holebelow the leak is stopped, permitting the cuttings and solid matter inthe fluid to precipitate and settlev about the bit and lower portion ofthe drill pipe, locking or freezing the pipe in the hole and frequentlycausing loss of the well.

It is to obviate such loss and to overcome the disadvantages aboverecited that I have devised the improvements herein disclosed.

What I claim and d esire to secure by Letters Patent is:

1. A device of the character described for use with drill pipe adaptedfor conducting fluid under high pressure including a coupling memberhaving a tapered socket, a packing ring slid.- able in the socket inresponse to thrust of a pipe member threaded into the socket and havinga concaved inner end exposed to pressure of fluid flowing through thecoupling member.

2. A device of the character described for use with drill pipe Aadaptedfor conducting fluid under pressure including a coupling member having atapered socket, a packing ring compressible'against the tapered wall ofthe socket by thrust of a pipe section inserted into the socket toprotect the coupling member against Wear incident to escape of fluidbetween the coupling member'and an inserted pipe section, saidvcompressible ring having a recess in its inner circumferential face anda relatively rigid reinforcing band in said recess.

3. A device of the character described for use 'with drill pipe adaptedfor conducting fluid under pressure including a coupling member havinga, tapered socket, a packing ring slidable in the socket in response tothrust of a pipe member threaded into. the socket and having a concavedinner end exposed to pressure of fluid flowing through the couplingmember, and means inside of and comprising a component -of said ring forrestraining inward bulging of the ring. under compression.

5. A device of the character described for use with drill pipe adaptedfor conducting fluid under pressure, including a coupling member havinga tapered socket, a packing ring slidable in the socket in response tothrust of a pipe member threaded into the socket and having a concavedinner end exposed to pressureof fluid flowing through the couplingmember, and means inside of and comprising a component of said ring forrestraining inward bulging of the ring under compression, said meanscomprising a relatively rigid band seated on the inner circumferentialside of the ring adjacent itsl concaved end. i

6. A device of the character described for use with drill pipe adaptedfor conducting fluid under pressure including a coupling member having atapered socket, a packing ring compressible against the tapered wall ofthe socket by thrust of a pipe section -inserted into the socket toprotect the coupling member against wear incident to escape of fluidbetween the coupling member and an inserted pipesection, and arelatively rigid reinforcing means in and comprising a, component ofsaid ring.`

7. A device of the character described for use with drill pipe adaptedfor `conducting fluid under pressure including a coupling member havinga tapered socket, a packing ring compressible against the tapered wallof the socket by thrustof a pipe section inserted -into the socket toprotect the coupling member against wear incident to escape of fluidbetween the coupling member and an inserted pipe section, and meansinside of and comprising a component of said ring for restraining inwardbulging of the ring imder compression, said means comprising a band oflesser thickness than that of said ring,` whereby said ring isrestrained against inward bulging for a portion only of its inner side.

FRANK J. HINDERLITER.

